From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt0-x241.google.com (mail-qt0-x241.google.com [IPv6:2607:f8b0:400d:c0d::241]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3zN3jt5mmczF0mY for ; Fri, 19 Jan 2018 12:52:34 +1100 (AEDT) Received: by mail-qt0-x241.google.com with SMTP id 33so466777qtv.1 for ; Thu, 18 Jan 2018 17:52:34 -0800 (PST) Sender: Ram Pai From: Ram Pai To: mpe@ellerman.id.au, mingo@redhat.com, akpm@linux-foundation.org, corbet@lwn.net, arnd@arndb.de Cc: linuxppc-dev@lists.ozlabs.org, linux-mm@kvack.org, x86@kernel.org, linux-arch@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, dave.hansen@intel.com, benh@kernel.crashing.org, paulus@samba.org, khandual@linux.vnet.ibm.com, aneesh.kumar@linux.vnet.ibm.com, bsingharora@gmail.com, hbabu@us.ibm.com, mhocko@kernel.org, bauerman@linux.vnet.ibm.com, ebiederm@xmission.com, linuxram@us.ibm.com Subject: [PATCH v10 17/27] powerpc: check key protection for user page access Date: Thu, 18 Jan 2018 17:50:38 -0800 Message-Id: <1516326648-22775-18-git-send-email-linuxram@us.ibm.com> In-Reply-To: <1516326648-22775-1-git-send-email-linuxram@us.ibm.com> References: <1516326648-22775-1-git-send-email-linuxram@us.ibm.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Make sure that the kernel does not access user pages without checking their key-protection. Signed-off-by: Ram Pai --- arch/powerpc/include/asm/book3s/64/pgtable.h | 19 +++++++++++++++++++ 1 files changed, 19 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/include/asm/book3s/64/pgtable.h b/arch/powerpc/include/asm/book3s/64/pgtable.h index e785c68..3d8186e 100644 --- a/arch/powerpc/include/asm/book3s/64/pgtable.h +++ b/arch/powerpc/include/asm/book3s/64/pgtable.h @@ -464,6 +464,25 @@ static inline void huge_ptep_set_wrprotect(struct mm_struct *mm, #ifdef CONFIG_PPC_MEM_KEYS extern bool arch_pte_access_permitted(u64 pte, bool write, bool execute); + +#define pte_access_permitted(pte, write) \ + (pte_present(pte) && \ + ((!(write) || pte_write(pte)) && \ + arch_pte_access_permitted(pte_val(pte), !!write, 0))) + +/* + * We store key in pmd/pud for huge pages. Need to check for key protection. + */ +#define pmd_access_permitted(pmd, write) \ + (pmd_present(pmd) && \ + ((!(write) || pmd_write(pmd)) && \ + arch_pte_access_permitted(pmd_val(pmd), !!write, 0))) + +#define pud_access_permitted(pud, write) \ + (pud_present(pud) && \ + ((!(write) || pud_write(pud)) && \ + arch_pte_access_permitted(pud_val(pud), !!write, 0))) + #endif /* CONFIG_PPC_MEM_KEYS */ #define __HAVE_ARCH_PTEP_GET_AND_CLEAR -- 1.7.1